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Update on model developments: Meteo-France Update on model developments: Meteo-France NWP model / clouds and turbulence NWP model / clouds and turbulence CLOUDNET workshop / Paris 27-28/05/2002 Jean-Marcel Piriou Centre National de Recherches Météorologiques Groupe de Modélisation pour l’Assimilation et la Prévision

Update on model developments: Meteo-France NWP model / clouds and turbulence CLOUDNET workshop / Paris 27-28/05/2002 Jean-Marcel Piriou Centre National

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Page 1: Update on model developments: Meteo-France NWP model / clouds and turbulence CLOUDNET workshop / Paris 27-28/05/2002 Jean-Marcel Piriou Centre National

Update on model developments: Meteo-France Update on model developments: Meteo-France NWP model / clouds and turbulenceNWP model / clouds and turbulenceUpdate on model developments: Meteo-France Update on model developments: Meteo-France NWP model / clouds and turbulenceNWP model / clouds and turbulence

CLOUDNET workshop / Paris 27-28/05/2002

Jean-Marcel PiriouCentre National de Recherches MétéorologiquesGroupe de Modélisation pour l’Assimilation et la Prévision

Page 2: Update on model developments: Meteo-France NWP model / clouds and turbulence CLOUDNET workshop / Paris 27-28/05/2002 Jean-Marcel Piriou Centre National

Summary

• How may 1D studies improve 3D models? Example of the How may 1D studies improve 3D models? Example of the

EUROCS project, links with CLOUDNETEUROCS project, links with CLOUDNET

• Clouds and turbulence: present developments and Clouds and turbulence: present developments and

perspectives of the ARPEGE/ALADIN NWP modelperspectives of the ARPEGE/ALADIN NWP model

Page 3: Update on model developments: Meteo-France NWP model / clouds and turbulence CLOUDNET workshop / Paris 27-28/05/2002 Jean-Marcel Piriou Centre National

PHYSICS

Global ARPEGEAquaplanet mode

SCM ARPEGE (EUROCS, GATE, TOGA,BOMEX, ARM, …)

LAM ALADIN / coupled / 10 km

Global stretched ARPEGE / 4DVAR-ass. / 20 to 200 km

Global regular ARPEGE / 4DVAR-ass. / 100 km

Page 4: Update on model developments: Meteo-France NWP model / clouds and turbulence CLOUDNET workshop / Paris 27-28/05/2002 Jean-Marcel Piriou Centre National

ARPEGE NWP ModelARPEGE NWP ModelJ.M. Piriou 2002J.M. Piriou 2002

IFS NWP ModelIFS NWP ModelBeljaars 2002Beljaars 2002

ObservationsObservationsYang and Slingo MWR 2001Yang and Slingo MWR 2001

Unified Climate ModelUnified Climate ModelYang and Slingo MWR 2001Yang and Slingo MWR 2001

Diurnal cycleof convection /

JJA

Page 5: Update on model developments: Meteo-France NWP model / clouds and turbulence CLOUDNET workshop / Paris 27-28/05/2002 Jean-Marcel Piriou Centre National

GCM picture from Colostate web page

Bring together a community of modelers : hierarchy of scales

LES & CRMs --- SCMs --- RCMs & GCMsobs obs

LES: Large Eddy SimulationCRM: Cloud Resolving ModelSCM: Single Column ModelRCM: Regional Climate ModelGCM: General Circulation Model

EUROCS : EUROpean Cloud Systems

Final aims: to improve the treatment of cloud systems in global and regional climate models

Links with GCSS (GEWEX Cloud System Study)

3-year project funded by theEuropean Union (Mar 2000 – Feb2003)

Concentrates on 4 major well identified deficiencies of climate models: stratocumulus over oceandiurnal cycle of shallow cumulus sensitivity of deep convection to mid-atmosphere humiditydiurnal cycle of deep convection over land

for more infos: www.cnrm.meteo.fr/gcss/EUROCS/EUROCS.html & J.-L. Redelsperger

z=

70m

to 6

00m

x= y= 1km

clouds

Page 6: Update on model developments: Meteo-France NWP model / clouds and turbulence CLOUDNET workshop / Paris 27-28/05/2002 Jean-Marcel Piriou Centre National

Diurnal cycle of deep convection(Françoise Guichard, Météo-France)

Page 7: Update on model developments: Meteo-France NWP model / clouds and turbulence CLOUDNET workshop / Paris 27-28/05/2002 Jean-Marcel Piriou Centre National

COMMON CRMs/SCMs CASE STUDY

Southern Great Plains

GCSS WG4 Case3a

4-day runs with deep convection occuringlarge-scale advections prescribed from observationsfixed surface heat fluxeswind nudged towards observedcyclic lateral boundary conditions

case part of the GCSS intercomparaison exercise for CRMs Xu et al. (2002) & SCMs (Xie et al. 2002)

ARM : Atmospheric Radiation measurement

1 : an « observed case » to assess our models over land (GCSS/ARM)

2 : building an « idealized case » to address the diurnal cycle of deep convection over land and its representation in models

Page 8: Update on model developments: Meteo-France NWP model / clouds and turbulence CLOUDNET workshop / Paris 27-28/05/2002 Jean-Marcel Piriou Centre National

THE IDEALIZED CASE

same framework of previous case except: 27 Mai 1997 of GCSS case 3 repeated twice large-scale vert. adv. (relatively weak) & prescribed surf. fluxes 48 h run, begins in the morning instead of the evening

rainfall events tend to occurs earlier in SCMs than CRMs (2 SCMs missing) + similar findings (e.g., noise & no or weak downdraughts)

results still preliminary, work in progress

Page 9: Update on model developments: Meteo-France NWP model / clouds and turbulence CLOUDNET workshop / Paris 27-28/05/2002 Jean-Marcel Piriou Centre National

before the development of deep convection

THE IDEALIZED CASE: transition regimes

(m)

SCM

CRM runs

MAX CLOUD TOP HEIGHT

a « shallow » non-precipitating transition period which last a

few hours in CRMs

Lx: 300 km

15 km

snapshots of cloud + rain water content in CRM run

transition phase: not represented

in several SCMs

Page 10: Update on model developments: Meteo-France NWP model / clouds and turbulence CLOUDNET workshop / Paris 27-28/05/2002 Jean-Marcel Piriou Centre National

THE IDEALIZED CASE : CIN

almost no CIN in SCM runs during daytime (true for at least 4 SCMs) ! apparently not simply a resolution problem

challenging for CRMs too strongly modulated by convective activity in CRMs runs, deep convection increases the CIN possibly related to convective downdraughts (?)

Page 11: Update on model developments: Meteo-France NWP model / clouds and turbulence CLOUDNET workshop / Paris 27-28/05/2002 Jean-Marcel Piriou Centre National

deep convection often occurs earlier than observed in SCMs runs too

no succession of dry-shallow-deep regimes in SCMs, dry to deep directly

complex sensitivity to triggering criteria & downdraughts formulation

no CIN during daytime & weak downdraughts ( a link?)

CONCLUSIONS from diurnal cycle of deep convection case

Page 12: Update on model developments: Meteo-France NWP model / clouds and turbulence CLOUDNET workshop / Paris 27-28/05/2002 Jean-Marcel Piriou Centre National

Diurnal cycle of shallow cumulus

(Geert Lenderink, KNMI)

Page 13: Update on model developments: Meteo-France NWP model / clouds and turbulence CLOUDNET workshop / Paris 27-28/05/2002 Jean-Marcel Piriou Centre National
Page 14: Update on model developments: Meteo-France NWP model / clouds and turbulence CLOUDNET workshop / Paris 27-28/05/2002 Jean-Marcel Piriou Centre National
Page 15: Update on model developments: Meteo-France NWP model / clouds and turbulence CLOUDNET workshop / Paris 27-28/05/2002 Jean-Marcel Piriou Centre National

EUROCS: Marine stratocumulus case

(Peter Duynkerke, IMAU)

Page 16: Update on model developments: Meteo-France NWP model / clouds and turbulence CLOUDNET workshop / Paris 27-28/05/2002 Jean-Marcel Piriou Centre National

EUROCS marine stratocumulus caseEUROCS marine stratocumulus case

Page 17: Update on model developments: Meteo-France NWP model / clouds and turbulence CLOUDNET workshop / Paris 27-28/05/2002 Jean-Marcel Piriou Centre National

Perspectives for the ARPEGE/ALADIN physics

• March towards new prognostic cloud and turbulence March towards new prognostic cloud and turbulence

variables: ql/i, qr/s, TKE, w_ud, w_ddvariables: ql/i, qr/s, TKE, w_ud, w_dd

• EUROCS: 4 validation cases EUROCS: 4 validation cases (next 12 months)(next 12 months)

• CLOUDNET: colocated ql/i, qr/s, PBL depth, cloudiness, CLOUDNET: colocated ql/i, qr/s, PBL depth, cloudiness,

close TEMP data to provide in-situ validation of new close TEMP data to provide in-situ validation of new

microphysics / turbulence microphysics / turbulence (in some months?)(in some months?)

Page 18: Update on model developments: Meteo-France NWP model / clouds and turbulence CLOUDNET workshop / Paris 27-28/05/2002 Jean-Marcel Piriou Centre National

Conclusions / perspectives

• During the last years 1D studies have become more and During the last years 1D studies have become more and

more important to develop and validate 3D models physical more important to develop and validate 3D models physical

packagespackages

• Both EUROCS (well posed lateral conditions) and Both EUROCS (well posed lateral conditions) and

CLOUDNET (long time series) will be used as a test-bed for CLOUDNET (long time series) will be used as a test-bed for

the new cloud physics and turbulencethe new cloud physics and turbulence